This application claims the priority of German Application No. 100 23 011.3 filed May 11, 2000, which is incorporated herein by reference.
This invention relates to a device which forms an integral part of a carding machine and which processes fiber material, particularly cotton, chemical fibers or the like. The carding machine includes a main carding cylinder followed by a doffer and a pull-off (withdrawing) device for the fiber material.
In a known apparatus, as disclosed, for example, in German Offenlegungsschrift (application published without examination) No. 23 64 262, two doffers are provided which take the fiber material off the main carding cylinder. The two doffers are disposed with respect to the carding cylinder and with respect to one another in such a manner that each doffer cooperates with both the carding cylinder and with the other, adjacent doffer and further, a web stripping device cooperates with one of the doffers. The two doffers rotate in opposite directions with respect to the main carding cylinder. An increased production rate is intended by the provision of the two doffers and their arrangement with respect to the carding cylinder and to one another. It is a condition of such a prior art arrangement that the carding cylinder process a fiber quantity which is approximately twice the usual amount handled by a carding cylinder. For such an increased fiber amount the cylinder clothing must be coarser to increase its processing capacity. This disadvantageously reduces the carding quality to a significant extent.
It is an object of the invention to provide an improved fiber processing device of the above-outlined type from which the discussed disadvantages are eliminated and with which a fiber web of increased specific weight may be obtained without adversely affecting the carding quality.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the carding machine includes a main carding cylinder and a doffer to which fiber material is transferred from the main carding cylinder and a fiber removing device positioned downstream of the doffer as viewed in an advancing direction of the fiber material through the carding machine. A gathering device including at least one gathering roll is disposed downstream of the doffer for effecting a negative draft on the fiber material between the doffer and the gathering roll.
The fiber gathering device, including at least one fiber gathering (fiber accumulating) roll, results in a negative draft of the fiber material: The gathering rolls accumulate and densify the fiber material, whereby an increased specific weight (quantity per surface or length) of the fiber web is obtained. The fiber web or sliver of increased specific weight is advantageously adapted for further processing, for example, into articles of hygiene.